Bis[(E)-N-(pyridin-3-yl­methyl­­idene)hydroxyl­amine-κN¹]silver(I) perchlorate

Each of the ions in the title salt, [Ag(C₆H₆N₂O)₂]ClO₄, is completed by the application of crystallographic twofold symmetry. The Ag^I atom is coordinated by two pyridine N atoms in an almost linear fashion [N—Ag—N = 170.0 (2)°], with the T-shaped coordination geometry being completed by a weakly associated perchlorate-O atom. Supra­molecular zigzag chains along [100] mediated by O—H⋯N hydrogen bonds [as parts of R₂²(6) loops] feature in the crystal packing. The perchlorate O atoms are disordered over two sets of sites in a statistical ratio.

Related literature

For structural diversity in the structures of silver salts, see: Kundu et al. (2010). For related structures, see: Abu-Youssef et al. (2010); Xu et al. (2012).

Experimental

Crystal data

• [Ag(C₆H₆N₂O)₂]ClO₄

• M_r = 451.58

• Monoclinic, C 2/c

• a = 15.382 (5) Å

• b = 8.234 (3) Å

• c = 13.320 (4) Å

• β = 111.531 (15)°

• V = 1569.3 (8) ų

• Z = 4

• Mo Kα radiation

• μ = 1.49 mm⁻¹

• T = 293 K

• 0.18 × 0.16 × 0.14 mm

Data collection

• Rigaku R-AXIS RAPID IP diffractometer

• Absorption correction: multi-scan (ABSCOR; Higashi, 1995) T_min = 0.449, T_max = 1.000

• 7501 measured reflections

• 1795 independent reflections

• 1176 reflections with I > 2σ(I)

• R_int = 0.052

Refinement

• R[F² > 2σ(F²)] = 0.048

• wR(F²) = 0.147

• S = 1.06

• 1795 reflections

• 129 parameters

• 34 restraints

• H-atom parameters constrained

• Δρ_max = 0.74 e Å⁻³

• Δρ_min = −0.49 e Å⁻³

Table 1
Selected bond lengths (Å)

Ag—N1	2.138 (5)
Ag—O2	2.843 (9)

Table 2
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O1—H1o⋯N2^i	0.84	2.07	2.821 (7)	148
Symmetry code: (i) -x+1, -y+1, -z+1.

Data collection: RAPID-AUTO (Rigaku, 1998); cell refinement: RAPID-AUTO; data reduction: CrystalClear (Rigaku/MSC, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Supporting information

S1. Comment

The structural diversity of nitrogen adducts of silver salts are well known with distinct coordination geometries and supramolecular patterns being observed even when only a simple change, for example, in counter-ion, is made (Kundu et al., 2010). The structural chemistry of pyridine-2-carboxaldoxime (LH) complexes with silver are relatively unexplored with only the Ag(LH)NO₃ salt (Abu-Youssef et al., 2010) and the salt co-crystal [C₁₂H₁₁AgN₄O₂]⁺[ClO₄]^-[C₁₂H₁₂AgN₄O₂] (Xu et al., 2012) having been reported previously. Herein, the crystal structure determination of the title salt, [Ag(C₆H₆N₂O)₂]ClO₄, (I), is described.

In (I), Fig. 1, each of the ions has crystallographic twofold symmetry. The Ag⁺ atom is coordinated by two N atoms in an almost linear array, Table 1. One of the perchlorate-O atoms is weakly associated with the silver atom so that the coordination geometry is T-shaped. The pyridine-2-carboxaldoxime ligand is planar as seen in the values of the C3—C4—C6—N2 and O1—N2—C6—C4 torsion angles of -2.3 (9) and -178.7 (5)°, respectively. The conformation about the imine bond [N2═C6 = 1.255 (7) Å] is E, and the nitrogen atoms are anti.

In the crystal packing, the oxime residues self-associate via O—H···N hydrogen bonds and six-membered {···HON}₂ synthons, Table 2. The result is the formation of a supramolecular chain with a zigzag topology along the a axis, Fig. 2.

Related literature

For structural diversity in the structures of silver salts, see: Kundu et al. (2010). For related structures, see: Abu-Youssef et al. (2010); Xu et al. (2012).

S2. Experimental

Silver perchlorate (1 mmol) and nicotinylaldehyde oxime (1 mmol) was dissolved in methanol solution (10 ml). The solution was filtered and set aside, away from light, for the growth of crystals. Colourless crystals deposited after several days.

S3. Refinement

Carbon- and oxygen-bound H-atoms were placed in calculated positions (C—H = 0.93 and O—H = 0.84 Å) and were included in the refinement in the riding model approximation, with U(H) set to 1.2–1.5U_eq(C,O).

The oxygen atoms of the perchlorate ion are disordered about a twofold rotation axis, and four oxygen atoms were given 0.5 occupancies. The Cl—O distances were restrained to 1.41±0.01 Å and the O···O distances to 2.30±0.01 Å. The anisotropic displacement parameters of the oxygen atoms were restrained to be nearly isotropic.

Computing details

Data collection: RAPID-AUTO (Rigaku, 1998); cell refinement: RAPID-AUTO (Rigaku, 1998); data reduction: CrystalClear (Rigaku/MSC, 2002); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: X-SEED (Barbour, 2001) and DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

Figures

	Fig. 1. The molecular structure of (I) showing displacement ellipsoids at the 20% probability level. Each ion has crystallographic twofold symmetry. Only one orientation for the disordered perchlorate anion is shown.
	Fig. 2. A view of the zigzag supramolecular chain along [100] in (I). The O—H···N hydrogen bonds are shown as orange dashed lines. Only one orientation for the disordered perchlorate anion is shown.

Bis[(E)-N-(pyridin-3-ylmethylidene)hydroxylamine- κN¹]silver(I) perchlorate

Crystal data

[Ag(C6H6N2O)2]ClO4	F(000) = 896
Mr = 451.58	Dx = 1.911 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 3613 reflections
a = 15.382 (5) Å	θ = 3.0–27.5°
b = 8.234 (3) Å	µ = 1.49 mm^−1
c = 13.320 (4) Å	T = 293 K
β = 111.531 (15)°	Prism, colourless
V = 1569.3 (8) Å^3	0.18 × 0.16 × 0.14 mm
Z = 4

Data collection

Rigaku R-AXIS RAPID IP diffractometer	1795 independent reflections
Radiation source: fine-focus sealed tube	1176 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.052
ω scan	θmax = 27.5°, θmin = 3.0°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)	h = −19→19
Tmin = 0.449, Tmax = 1.000	k = −10→10
7501 measured reflections	l = −17→17

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.147	H-atom parameters constrained
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0776P)^2 + 1.2356P] where P = (Fo^2 + 2Fc^2)/3
1795 reflections	(Δ/σ)max = 0.001
129 parameters	Δρmax = 0.74 e Å^−3
34 restraints	Δρmin = −0.49 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq	Occ. (<1)
Ag	1.0000	0.04678 (8)	0.7500	0.0718 (3)
Cl	1.0000	−0.4118 (3)	0.7500	0.0779 (6)
O1	0.5863 (3)	0.6168 (5)	0.5648 (4)	0.0819 (13)
H1o	0.5297	0.6370	0.5298	0.123*
N1	0.8519 (3)	0.0695 (5)	0.6720 (4)	0.0573 (11)
N2	0.6021 (3)	0.4515 (5)	0.5606 (4)	0.0603 (12)
C1	0.7951 (4)	−0.0529 (6)	0.6259 (5)	0.0617 (14)
H1	0.8207	−0.1559	0.6285	0.074*
C2	0.7003 (4)	−0.0342 (7)	0.5744 (5)	0.0645 (14)
H2	0.6630	−0.1234	0.5437	0.077*
C3	0.6612 (4)	0.1150 (7)	0.5686 (4)	0.0587 (13)
H3	0.5971	0.1289	0.5337	0.070*
C4	0.7187 (3)	0.2477 (6)	0.6158 (4)	0.0495 (11)
C5	0.8130 (3)	0.2174 (7)	0.6658 (4)	0.0544 (12)
H5	0.8521	0.3044	0.6971	0.065*
C6	0.6859 (4)	0.4136 (7)	0.6113 (4)	0.0571 (12)
H6	0.7283	0.4943	0.6469	0.068*
O2	1.0050 (8)	−0.2768 (10)	0.6778 (8)	0.105 (3)	0.50
O3	0.9040 (6)	−0.4057 (13)	0.7376 (10)	0.110 (4)	0.50
O4	1.0044 (7)	−0.5524 (9)	0.6836 (7)	0.089 (3)	0.50
O5	1.0649 (10)	−0.4065 (18)	0.8439 (7)	0.171 (6)	0.50

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ag	0.0392 (4)	0.0813 (5)	0.0859 (5)	0.000	0.0121 (3)	0.000
Cl	0.0624 (13)	0.0605 (12)	0.1049 (17)	0.000	0.0238 (13)	0.000
O1	0.064 (3)	0.054 (2)	0.106 (3)	0.005 (2)	0.005 (3)	0.007 (2)
N1	0.042 (2)	0.061 (3)	0.063 (3)	−0.0016 (19)	0.013 (2)	0.000 (2)
N2	0.054 (3)	0.054 (3)	0.066 (3)	0.005 (2)	0.013 (2)	0.006 (2)
C1	0.056 (3)	0.051 (3)	0.072 (3)	0.000 (2)	0.017 (3)	0.000 (3)
C2	0.048 (3)	0.058 (3)	0.075 (4)	−0.009 (3)	0.009 (3)	−0.006 (3)
C3	0.040 (3)	0.068 (3)	0.060 (3)	−0.003 (3)	0.009 (2)	0.002 (3)
C4	0.043 (2)	0.055 (3)	0.045 (2)	−0.006 (2)	0.010 (2)	0.002 (2)
C5	0.040 (3)	0.059 (3)	0.057 (3)	−0.005 (2)	0.010 (2)	−0.003 (2)
C6	0.045 (3)	0.057 (3)	0.062 (3)	−0.004 (2)	0.010 (2)	0.002 (2)
O2	0.123 (7)	0.082 (5)	0.125 (7)	−0.002 (5)	0.063 (6)	0.020 (5)
O3	0.098 (7)	0.104 (6)	0.148 (8)	−0.010 (6)	0.068 (7)	−0.018 (6)
O4	0.072 (5)	0.074 (5)	0.107 (6)	0.006 (4)	0.018 (5)	−0.014 (4)
O5	0.166 (11)	0.162 (9)	0.137 (9)	−0.001 (9)	−0.001 (8)	−0.008 (8)

Geometric parameters (Å, º)

Ag—N1^i	2.138 (5)	C2—H2	0.9300
Ag—N1	2.138 (5)	C3—C4	1.402 (8)
Ag—O2	2.843 (9)	C3—H3	0.9300
O1—N2	1.387 (7)	C4—C5	1.378 (7)
O1—H1o	0.8400	C4—C6	1.449 (8)
N1—C1	1.327 (7)	C5—H5	0.9300
N1—C5	1.346 (7)	C6—H6	0.9300
N2—C6	1.255 (7)	Cl—O5	1.283 (7)
C1—C2	1.374 (9)	Cl—O3	1.426 (7)
C1—H1	0.9300	Cl—O4	1.474 (6)
C2—C3	1.357 (8)	Cl—O2	1.490 (6)
N1^i—Ag—N1	170.0 (2)	C5—C4—C3	117.1 (5)
N1^i—Ag—O2	95.1 (3)	C5—C4—C6	118.6 (5)
N1—Ag—O2	94.2 (3)	C3—C4—C6	124.3 (5)
N2—O1—H1o	109.5	N1—C5—C4	124.0 (5)
C1—N1—C5	117.2 (5)	N1—C5—H5	118.0
C1—N1—Ag	124.1 (4)	C4—C5—H5	118.0
C5—N1—Ag	118.6 (3)	N2—C6—C4	122.0 (5)
C6—N2—O1	112.5 (5)	N2—C6—H6	119.0
N1—C1—C2	122.9 (5)	C4—C6—H6	119.0
N1—C1—H1	118.6	O5—Cl—O3	120.9 (7)
C2—C1—H1	118.6	O5—Cl—O4	114.9 (7)
C3—C2—C1	119.8 (5)	O3—Cl—O4	103.4 (5)
C3—C2—H2	120.1	O5—Cl—O2	113.4 (7)
C1—C2—H2	120.1	O3—Cl—O2	101.3 (5)
C2—C3—C4	119.1 (5)	O4—Cl—O2	100.0 (5)
C2—C3—H3	120.5	Cl—O2—Ag	117.8 (5)
C4—C3—H3	120.5
N1^i—Ag—N1—C1	168.7 (5)	Ag—N1—C5—C4	178.7 (4)
O2—Ag—N1—C1	9.2 (5)	C3—C4—C5—N1	−0.4 (8)
N1^i—Ag—N1—C5	−9.2 (4)	C6—C4—C5—N1	−177.8 (5)
O2—Ag—N1—C5	−168.7 (4)	O1—N2—C6—C4	−178.7 (5)
C5—N1—C1—C2	−0.7 (9)	C5—C4—C6—N2	175.0 (5)
Ag—N1—C1—C2	−178.7 (5)	C3—C4—C6—N2	−2.3 (9)
N1—C1—C2—C3	0.5 (10)	O5—Cl—O2—Ag	−57.3 (9)
C1—C2—C3—C4	−0.2 (9)	O3—Cl—O2—Ag	73.9 (7)
C2—C3—C4—C5	0.1 (8)	O4—Cl—O2—Ag	179.9 (5)
C2—C3—C4—C6	177.4 (5)	N1—Ag—O2—Cl	−93.0 (6)
C1—N1—C5—C4	0.7 (8)

Symmetry code: (i) −x+2, y, −z+3/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O1—H1o···N2^ii	0.84	2.07	2.821 (7)	148

Symmetry code: (ii) −x+1, −y+1, −z+1.

 

Footnotes

‡Additional correspondence author, e-mail: [e-mail].